Transcript Slide 1

What is a Mixture?
 A mixture is two or more substances that have been combined
physically but not chemically





Mixtures can be separated by physical means
When substances in a mixture combine, only some of their physical
properties change (ex: color; texture)
Substances keep their chemical properties
 Ex: In a mixture of soil and water, the soil is still brown with specific
minerals, and the water is still a liquid with a density of 1.0 g/ml
A mixture has no definite chemical composition
When you chemically combine substances, most of their physical
properties change into an entirely new substance.


Ex: burnt sugar is now all caramel
Ex: but a mixture of Chex Mix contains different foods
Types of Mixtures:
 A homogeneous mixture is a mixture in which all
substances appear all one color

Examples: milk, juice, salt and sugar, food coloring
and water
 A heterogeneous mixture is a mixture in which
substances have more than one color

Examples: salad, trail mix, sand and water
Ways to separate a Mixture:
 Filtration – separates bigger particles from smaller particles

Ex: sand and water
 Evaporation – some particles turn to gas & others stay behind

Ex: salt and water -to get the salt only
 Distillation – evaporating a liquid and then condensing it again

Ex: salt and water-to get both salt and water separated
 Magnetism – separating a mixture where one substance has
magnetic properties

Ex: a pile of paperclips and rubber bands
Filtration
•Mixtures can be separated by filtering
if the particles of one substance are
larger than the other substance
•Ex: A mixture of sand and water is
separated using the filtration system
pictured.
•Sand would be found in the filter paper
•Water would be found in the beaker
•Since sand particles sink in water, they
are large enough to get stuck in the
filter
•Salt particles are too small to get stuck
in a filter
Distillation
Distillation
 Distillation (evaporation and condensation) is
used to separate a mixture such as saltwater,
where the particles are too small to be filtered
 Water is heated and evaporates, leaving the salt
behind
 The water vapor is then collected in another
tube and cooled
 The water vapor condenses and re-collects in
another container
 This method allows you to purify water, vinegar,
and other impure liquids
Filtration
Distillation